Abstract : Recent observations and geodetic measurements in the European Alps show thatchanges are occurring on rock glacier dynamics, ranging from moderate velocityvariations to strong acceleration or even total collapse. These changes can berelated to the ground temperature and to climate warming. In most cases, rockglaciers do not represent any serious hazard, except the instability of their surfaceand local rockfalls at the steep front. The surface movements, though moderate,can nevertheless cause damages to sensible infrastructures like cableways orbuildings, if these are not designed to adapt to surface movements. The strongaccelerations observed on some rock glaciers, however, induce a change ofmagnitude, and may threaten in some cases downslope areas. Thus, the presence ofactive or inactive rock glaciers with high ice content must be considered not onlywith regard to present conditions and dynamics, but with respect to possibleevolutions due to climate change.